1. Field of the Invention
This invention refers to a metal reducing furnace, and more particularly to a center backfire inner heat regenerative energy saving high efficiency furnace and tank integration reduction furnace system which is used for refining magnesium.
2. Description of the Prior Art
The traditional magnesium refining technology is called Pidgeon which uses a horizontal furnace. Plural reduction tanks are distributed horizontally inside the furnace. The reduction tanks are filled up with reactant pellet. Firstly the reduction tanks are heated up by the outside radiant heat of reverberator, afterwards the reduction tanks transmit the heat radiation to the reactant pellet, and then the pellet mutually relay transmits heat. This is a peripheral heating (as shown in FIG. 5). If using this kind of heating method, continuous experiments prove that the heat transmission rate is low within the reduction tank, the temperature gradient is high, the temperature evenness is not good, and the transmission diameter of the heat radiation is big. Because of the above reasons, it takes a long period of time (10-12 hours a cycle) to let the material within the tank reach its reduction temperature (1150-1200° C.). Besides that, the volume of the reduction tank is too small and every time it can only stuff several hundred kilograms of material. It needs more furnaces and tanks to reach the production requirement. The method of Piegeon has many drawbacks, such as low efficiency, high labor intensity, energy consuming, low yielding of the magnesium, and environmental pollution.